There are no large coronal holes on the Earthside of the sun. Credit: SDO/AIA.

SPACE WEATHERNOAA Forecasts

Updated at: 2012 Jan 19 2200 UTC

FLARE

0-24 hr

24-48 hr

CLASS M

50 %

50 %

CLASS X

05 %

05 %

Geomagnetic Storms:Probabilities for significant disturbances in Earth's magnetic field are given for three activity levels: active, minor storm, severe storm

Updated at: 2012 Jan 19 2200 UTC

Mid-latitudes

0-24 hr

24-48 hr

ACTIVE

10 %

15 %

MINOR

01 %

05 %

SEVERE

01 %

01 %

High latitudes

0-24 hr

24-48 hr

ACTIVE

15 %

25 %

MINOR

01 %

10 %

SEVERE

01 %

05 %

Thursday, Jan. 19, 2012

What's up in space

Metallic photos of the sun by renowned photographer Greg Piepol bring together the best of art and science. Buy one or a whole set. They make a stellar gift.

EARTH-DIRECTED SOLAR FLARE: Active sunspot 1401 erupted today, Jan. 19th, between 15:15 and 16:30 UT. The long-duration blast produced an M3-class solar flare and a CME that appears to be heading toward Earth. This movie from the Solar Dynamics Observatory shows the extreme UV flash:

NASA's twin STEREO spacecraft recorded an impressive CME emerging from the blast site: movie #1, movie #2. Analysts at the Goddard Space Weather Lab confirm that the CME is heading for Earth, and they say strong geomagnetic storms are possible (although not guaranteed) when the cloud arrives this weekend. Their animated forecast track predicts an impact on Jan. 21st at 22:30 UT (+/- 7 hrs). Aurora alerts:text, voice.

INCREASING SOLAR ACTIVITY CLEANS UP SAT-DEBRIS: Earth's atmosphere has been puffing up in response to increasing levels of UV radiation from sunspots. This is good news for satellite operators, because a puffed up atmosphere helps clean up low-Earth orbit. "The number of cataloged debris in Earth orbit actually decreased during 2011," reports Nick Johnson in NASA's Orbital Debris Quarterly newsletter. "[The figure below] illustrates how the rate of debris reentries from the Fengyun-1C anti-satellite test of January 2007 increased during the past year."

"Even though only 6% of the total 3218 cataloged debris from the ill-advised engagement had reentered by the end of 2011, half of these debris fell out of orbit in the past 12 months," he points out. "Likewise, many debris from the 2009 accidental collision of Cosmos 2251 and Iridium 33 are accelerating their departure from Earth orbit. In the absence of a new major satellite breakup, the overall orbital debris population should continue to decrease during 2012 and 2013."

ADVANCING SUNSPOTS: A phalanx of sunspots is turning toward Earth. Their advance is documented in this two-day movie from the Solar Dynamics Observatory:

The large one in the middle, AR1401, has a "beta-gamma" magnetic field that harbors energy for M-class solar flares. At the moment it is unleashing one such flare every day, such as this flash recorded during the late hours of Jan. 19th. Eruptions from AR1401 will become increasingly geoeffective in the days ahead as the sun's rotation aligns the active region with our planet.

Potentially Hazardous Asteroids (PHAs) are space rocks larger than approximately 100m that can come closer to Earth than 0.05 AU. None of the known PHAs is on a collision course with our planet, although astronomers are finding new ones all the time.